In a first prior art optical pick-up device, it is necessary to arrange 3-dimensionally optical elements such as a semiconductor laser device, a prism, a collimator lens, etc. with a high precision. Heretofore, in order to position and fix these optical elements with a high precision, a frame is used. Since different optical elements have different forms and postures, with which they are mounted on the frame, it should have a complicated shape. Therefore, heretofore, it is fabricated by a one-body formation such as die casting, resin mold, etc.
Second prior art optical pick-up devices, which are used in an optical disk device, an opto-magnetic device, etc. are classified into those of thin portable type, and those of standard type for home use and each of them is mounted on a frame formed in one body, which is exclusively used either for those of thin type or for those of standard type.
Third prior art optical pick-up devices, which are used in an optical disk device, an opto-magnetic disk device, etc, are fabricated by positioning optical elements such as a semiconductor laser device, a lens, a prism, etc. on a frame having a one-body-structure from one open side and fixing them, the whole side being closed thereafter by a cover.